Imagine undergoing major surgery for ovarian cancer, where the procedure itself is a battle against the disease, but the real agony hits afterward with relentless pain that could derail your recovery. That's the harsh reality for countless patients, and understanding how to manage it effectively is crucial. In this piece, we'll dive into groundbreaking research on butorphanol, an alternative to traditional opioids, and explore how varying doses impact pain relief after ovarian cancer surgeries. But here's where it gets intriguing: Could this drug not only ease suffering but also shield your immune system from the toll of surgery? Stick around as we unpack the study that might change how we think about postoperative care for cancer patients.
Introduction
Ovarian cancer ranks as the third most prevalent gynecological malignancy worldwide, with survival rates hovering between 40% and 45% over five years. This grim statistic underscores the urgency of aggressive treatments, such as cytoreductive surgery, which often involves removing multiple organs to excise the cancer. Unfortunately, these operations bring about a cascade of intense pain types—incisional from the cuts, inflammatory responses swelling the tissues, and visceral discomfort from internal disruptions—leading to excruciating postoperative suffering that can hinder healing. Effective pain control post-surgery isn't just about comfort; it's a cornerstone of protocols like Enhanced Recovery After Surgery (ERAS), which emphasize opioid analgesics to get patients back on their feet faster.
Enter butorphanol, a synthetic opioid that acts as both an agonist and antagonist on opioid receptors. Its affinity is notably skewed: potent on κ receptors (ratio of 25:4:1 against κ, μ, and δ, respectively), which gives it a unique edge in targeting visceral pain over pure μ agonists. This dual action helps curb the nasty side effects of opioids, like dependency and respiratory issues, while providing solid relief. Studies back this up; for instance, one trial by Du and colleagues combined butorphanol with dexmedetomidine for patients having laparoscopic hysterectomies, slashing visual analog scale (VAS) scores for pain, curbing nausea and vomiting, and boosting overall satisfaction. Another investigation revealed butorphanol's prowess in easing visceral pain after microwave ablation for liver tumors. Yet, despite these promising findings, its role in extensive open abdominal procedures like ovarian cancer surgery has remained unexplored. With the literature highlighting butorphanol's pharmacology and the glaring need for better analgesia in ovarian cancer cases, we're optimistic that patient-controlled intravenous analgesia (PCIA) using butorphanol could deliver robust pain management with fewer downsides. But the big question lingers: What's the ideal dosage to strike that balance?
Adding another layer, cancer patients often grapple with weakened immune systems, making them prime targets for immune suppression during the perioperative phase. Surgical stress, coupled with inflammation, anesthesia, and even the procedure itself, can scatter tumor cells and trigger a defense shutdown. Research in vitro shows butorphanol safeguarding PC12 cells from inflammation and cell death induced by oxygen-glucose deprivation followed by reperfusion—a common mimic of surgical trauma. Moreover, butorphanol seems to curb the aggressive traits of ovarian cancer cells by reducing TMEFF1 (also known as tomoregulin-1), a protein that promotes cancer spread. Based on this, we theorize that butorphanol PCIA, as a mixed opioid agonist-antagonist, might bolster immune stability in ovarian cancer patients post-cytoreductive surgery.
Materials and Methods
Our investigation was a prospective, double-blind, randomized controlled trial, ethically approved by the Medical Research Ethics Committee at the First Affiliated Hospital of the University of Science and Technology of China (approval number: 2021KY [258]). It also received clearance from the Chinese Clinical Trial Registry (ChiCTR 2300069879). We adhered strictly to the Declaration of Helsinki and CONSORT guidelines, with all participants providing written informed consent.
Patients
We recruited individuals slated for primary cytoreductive surgery at the First Affiliated Hospital of the University of Science and Technology of China (also known as Anhui Provincial Hospital) from May 2023 through March 2025. Eligible candidates met these criteria: ASA physical status classification of I, II, or III; confirmed ovarian cancer via surgical and pathological tests; no allergies to the trial medications; FIGO stages I through III; and ages between 18 and 65. Exclusions applied to those with multiple chronic illnesses, inability to handle anesthesia, severe heart or kidney problems, clotting disorders, allergies to sufentanil or butorphanol, significant neurological deficits, advanced cachexia from ovarian cancer, prior opioid use, recent infections or immune conditions, or pregnancy/lactation. We also disqualified cases with intraoperative blood loss exceeding 2000 mL, surgeries lasting over 6 hours, or the need for a second procedure within 48 postoperative hours.
Four groups emerged from random assignment based on postoperative PCIA regimens: S (sufentanil at 0.04 μg·kg⁻¹·h⁻¹), B1 (butorphanol at 3.0 μg·kg⁻¹·h⁻¹), B2 (butorphanol at 3.5 μg·kg⁻¹·h⁻¹), and B3 (butorphanol at 4.0 μg·kg⁻¹·h⁻¹).
Anesthesia and Analgesia
Preparation began with an 8-hour fast and 4 hours without oral intake. General anesthesia kicked off with endotracheal intubation. Upon arrival in the operating room, we verified patient details, secured IV access, and monitored vitals: heart rate via ECG, oxygen levels, and end-tidal CO₂. Radial artery catheterization tracked blood pressure, while internal jugular vein access monitored central venous pressure. All groups received induction via midazolam (0.05 mg/kg), sufentanil (0.5 μg/kg), etomidate (0.3 mg/kg), and rocuronium (0.8 mg/kg). Muscle relaxation confirmed intubation, followed by intermittent positive pressure ventilation. Propofol targeted 2.0–4.0 μg/mL plasma levels, remifentanil 2.0–6.0 ng/mL, sevoflurane at 1–2%, and cisatracurium boluses (0.1 mg/kg) kept the Bispectral Index at 40–60. We managed thermal protection with nasal temperature checks and adjusted acid-base, electrolytes, blood glucose, and other parameters per arterial blood gas tests.
Post-surgery, every patient got bilateral ultrasound-guided four-point transversus abdominis plane (TAP) blocks, delivering 15 mL of 0.25% ropivacaine per side via varied needle paths for targeted pain control.
For postoperative analgesia, PCIA was standard across groups. Envelopes sealed the protocols, randomized for distribution. An independent anesthetic nurse prepared the pumps, while an anesthesiologist handled outcome data. Formulations included: sufentanil at 0.04 μg·kg⁻¹·h⁻¹ for group S; low-dose butorphanol at 3.0 μg·kg⁻¹·h⁻¹ for B1; medium-dose at 3.5 μg·kg⁻¹·h⁻¹ for B2; and high-dose at 4.0 μg·kg⁻¹·h⁻¹ for B3. Each ran at 2 mL/h background infusion, with 1 mL bolus doses and a 30-minute lockout. If VAS pain scores hit 4 or above, we provided rescue analgesia: a 50 mg IV bolus of flurbiprofen axetil.
Data Collection
We logged baseline patient details like age, height, weight, BMI, and ASA scores. Surgical metrics included duration, blood loss, urine output, fluid intake, extubation time, and complexity scores. Postoperative VAS pain ratings came at 2h (T1), 6h (T2), 12h (T3), 24h (T4), and 48h (T5), plus the area under the VAS-time curve (AUCVAS-time) over 48 hours—a measure of overall pain burden. We also tracked PCA button presses, rescue analgesia needs, side effects, recovery milestones, and inflammatory markers pre- and post-op: neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and lymphocyte-to-monocyte ratio (LMR).
Lymphocyte subsets were quantified at baseline and 48 hours post-op via flow cytometry on an Attune NxT analyzer: CD3+ T cells, CD19+ B cells, CD3+CD4+ helper T cells, CD3+CD8+ cytotoxic T cells, CD3-CD16+CD56+ natural killer (NK) cells, and the CD4+/CD8+ ratio. Figure 1 illustrates the gating strategy and data plots for each group. To sidestep confounding from chemo, we barred those with recent neoadjuvant therapy, and all blood draws occurred before any post-op chemo.
Statistical Analysis
A pilot with 10 per group yielded VAS scores at 12h: B1 (3.5 ± 0.85), B2 (2.80 ± 0.63), B3 (2.60 ± 0.70), S (2.9 ± 0.74). Power analysis via PASS 15.0, with 90% confidence and α=0.05, set sample size via one-way ANOVA averaging to 69. Factoring 20% dropout, we aimed for 88 total, or 22 per group.
Analysis used SPSS 25.0. Normally distributed data got mean ± SD; skewed data, median and IQR. ANOVA compared group means, with Bonferroni corrections. Categorical data faced non-parametric tests: chi-square for unordered, rank-sum for ordered, Fisher’s exact for sparse cells. Significance: α=0.05, two-tailed.
Results
From 119 ovarian cancer surgery candidates under general anesthesia from May 2023 to March 2025, 88 joined and got randomized (Figure 2). Table 1 confirms no baseline differences in age, BMI, ASA, comorbidities, blood loss, surgery time, extubation, complexity scores, intraoperative fluids, or bleeding (all P>0.05).
Postoperative Pain Score
At 2 and 6 hours, VAS scores showed no group gaps (P=0.789 and 0.154). By 24 hours, B3 edged below S (P=0.042). B2 and B3 outperformed B1 at 12 and 24 hours (P=0.007, <0.001 for B2; 0.005, <0.001 for B3). No differences between B2 and B3 at any point (P=1.000 across). AUCVAS-time was higher in B1 vs. S (P=0.010) but lower in B3 (P=0.004); B2 and B3 dipped below B1 (P<0.001), per Figure 4.
PCIA and Rescue Analgesia
Effective presses dipped in B3 vs. S (P=0.045) and B1 (P=0.005). Total presses even across groups (P=0.075). Rescue needs dropped in B3 vs. B1 (P=0.002), as in Table 2.
Comparison of Adverse Effects and Postoperative Rehabilitation Indexes Among the Four Groups
No differences in nausea/vomiting, dizziness, drowsiness, respiratory issues, or complications like fistulas, lung problems, or wound issues (P>0.05), per Table 3. Recovery times (first flatus, ambulation, hospital stay) matched, but ambulation sped in B3 vs. S (P=0.031).
Comparison of Inflammatory Biomarkers Among the Four Groups
PLR and NLR rose post-op in all, LMR fell. No intergroup variances pre- or post- (Figure 5).
Expression of CD3+, CD4+, CD8+, CD4+/CD8+, and CD3‐CD16+CD56+
No group differences at T0 or T5 (P>0.05), as in Figure 6. S saw NK cell drops and CD19+ B cell hikes at T5 vs. T0 (P=0.007, 0.005). B1 had CD19+ B cell, CD4+ T cell, and CD4+/CD8+ ratio increases, CD8+ T cell decreases (P=0.012, 0.007, 0.014, 0.011). B2 and B3 unchanged in subsets and NK (P>0.05).
Discussion
This research assessed butorphanol PCIA's effects on pain relief and immunity in ovarian cancer cytoreductive surgery patients. Findings point to optimal analgesia at 4.0 μg·kg⁻¹·h⁻¹ butorphanol under intubated general anesthesia, minus extra side effects, with no major immune shifts—making it a safe postoperative choice.
Studies note sufentanil's analgesia as 1000x morphine's, butorphanol's 5–8x, equating 1 mg sufentanil to 200 mg butorphanol. Another trial pitted dexmedetomidine plus sufentanil (2.0 μg/kg) or butorphanol (0.15 mg/kg) in laparoscopic GI tumor resections, deeming both safe. To dodge high-dose risks, we tested butorphanol at 3.0, 3.5, 4.0 μg·kg⁻¹·h⁻¹ vs. sufentanil 0.04 μg·kg⁻¹·h⁻¹.
Butorphanol's κ-agonist perks aid visceral pain while limiting opioid woes. TAP blocks handle incisional pain but not visceral, lasting 12–24 hours per drug and patient. Our VAS peaks at 12h (B1: 3.27±0.77, B2: 3.73±0.83, B3: 3.00±0.62, S: 2.73±0.63) suggest TAP wear-off, ramping PCIA needs. Medium/high doses shone post-12h, with significant VAS drops at 12–24h (P<0.001). B2/B3 beat B1 at 12h (P=0.007/<0.001), showing low dose's inadequacy. B3 outpaced S at 24h (P=0.042), mirroring sufentanil's potency.
AUCVAS-time comparisons showed B1 worse than S (P=0.010), B3 better (P=0.004); B2/B3 superior to B1 (P<0.001). Sufentanil/butorphanol with TAP managed short-term pain well, but B1 fell short for ovarian cases. B3 excelled over S, with fewer presses and rescues. Thus, 4.0 μg·kg⁻¹·h⁻¹ butorphanol optimized relief.
Side effects matched across groups. Meta-analyses confirm butorphanol PCA cuts nausea, vomiting, itch, dizziness. Drowsiness in six B3 patients (mild, no intervention) echoed butorphanol norms, yet insignificant vs. S. No respiratory hits. Earlier ambulation in B3 vs. S likely tied to better pain control and recovery drives. But single-center limits call for larger, multi-site trials.
Inflammatory markers like NLR, PLR, LMR gauge cancer risk; NLR signals opioid immunosuppression post-thoracoscopy. Here, post-op PLR/NLR hikes and LMR drops indicated stress-induced inflammation and clotting risks. No group differences meant butorphanol mirrored sufentanil's inflammatory impact.
NK cells, key in innate immunity for killing cells and boosting cytokines, are cancer targets. S saw NK drops post-op (P=0.007), aligning with sufentanil's suppression. Butorphanol groups held steady, implying no NK harm.
Opioids influence immunity via cells (neutrophils, macrophages, NK) and pathways like HPA axis or nerves. B1 had CD19+ B cell, CD4+ T cell, CD4+/CD8+ hikes, CD8+ T drops—hinting partial immune strain. B2/B3 stayed flat, suggesting higher doses eased stress immunosuppression mildly. μ-agonists hinder T/macrophage functions, fueling tumors via μ-receptors while dampening immunity. Morphine curbs antitumor responses via macrophages/T cells. Butorphanol, via κ, relieves pain and curbs μ-driven immunosuppression. It protects against ischemia-reperfusion, boosting macrophages and cytokines. Our data support butorphanol's balanced immune role.
B1's analgesia shortfall let B2/B3 shine without immune cost. Though no overt enhancement, medium/high doses mitigated surgical immunosuppression. Higher butorphanol might preserve immunity, aiding ovarian outcomes. And this is the part most people miss: Weighing benefits for cancer patients, high-dose butorphanol (4.0 μg·kg⁻¹·h⁻¹) PCIA suits ovarian cytoreductive analgesia, even if it doesn't fully boost immunity. Limitations include single-center scope, short 48h follow-up, and focus on cell counts over function. Broader, long-term multicenter studies are needed.
Conclusion
High-dose butorphanol (4.0 μg·kg⁻¹·h⁻¹) PCIA powerfully combats postoperative pain, hastens ambulation, and leaves immune markers untouched in 48 hours. For adults facing primary ovarian cancer cytoreductive surgery, it's a top recommendation.
Data Sharing Statement
Anonymized participant data won't be publicly shared due to sensitive clinical details. Consent forms lack public sharing clauses. Methodologically solid requests to the corresponding author (Wei Zhang, doctor_zw97079@163.com) will be reviewed by the steering committee, potentially granting access via agreement.
Funding
Chen Xiao-ping Foundation for the Development of Science and Technology of Hubei Province funded this via Rui Research Special Funds.
Disclosure
Authors declare no conflicts of interest.
References
[Same as original, listed here for completeness.]
What do you think—could butorphanol revolutionize pain management for cancer surgeries, or are we overlooking risks to immune health? Do you agree high doses are worth it for better recovery, or should we stick with traditional opioids? Share your thoughts and join the conversation in the comments; let's debate the future of perioperative care!
